I need some header input!

Heres the question:
How much hp would I lose going from the headers I already have, some hooker super comps with 1 3/4 tubes, to a normal set of smash the header under the tie rod 1 5/8 tubes? The reason I ask is that I have a 73' Dart Sport 340 that someone installed an earlier style Kmember in. If I were running manual steering, that makes it perfect for using the SC headers I already have. But, I'd like to use the spool mount, and power steering, if I wouldn't lose a ton of HP going to smaller tubes. I could sell my Kmember/5204 headers/manual box/etc and get the parts I need without much cash outlay in the end.

Heres the combo:
I have a 422 stroker/1970 340 block. Decks cut parallel, main studs/girdle and alignhoned. bored/plate honed, bushed lifter bores, priority main oiling and other oiling mods. The previous owner built the shortblock, and I got the receipts for everything. Since it was very low miles/runs, I didn't tear it all the way down so I don't know exactly what has been done to the oiling system. I do know he didn't spare any expense when he was building it. All forged bottom end, h-beams, JE pistons, Fluidamper, etc all balanced.

I have a cam that is getting reground by Bullit, it will be .604/.600 lift 245/[email protected]. I forget the rest of the specs off hand. Its a solid roller.

Set of Edelbrock RPM heads that I'll probably port myself and have a good valve job/guides checked. Crane Gold rockers, etc. As of right now, its got a Victor 340 intake, but thats another issue in itself.


So, what do you guys think? Stick with the biscuit K, manual steering, and big tubes, or go with PS, small tubes, and the correct front suspension? I will be doing more cruising and street bruising than anything, Quaker City Raceway is twenty minutes away from me but I don't think I'll have the time to go too often. Midrange torque and HP is my favorite feeling. I'll give a little up in the higher RPMs any day. What should I do.